When ordinary light is made incident on a quarter wave plate, the emergent light is
(a) linearly polarised.
(b) circularly polarised.
(c) unpolarised.
(d) elliptically polarised.
(a) linearly polarised.
(b) circularly polarised.
(c) unpolarised.
(d) elliptically polarised.
(d) elliptically polarised
The wavefront due to a source situated at infinity is
(a) spherical
(b) cylindrical
(c) planar
(d) circular
The angle of incidence at which reflected light is totally polarised for reflection from air to glass (refractive index n) is
Which of the following is conserved when light waves interference?
(a) phase.
(b) intensity.
(c) amplitude.
(d) none of these.
In the Young double slit experiment, the fringe pattern as seen on the screen is:
(a) parabola
(b) Hyperbola
(c) Ellipse
(d) Spiral
The wave-front due to source situated at the infinity is
(A) Spherical
(B) Cylindrical
(C) Plane
(D) Rectangular
Wavefront is the locus of all points, where the particles of the medium vibrate with the same
(a) phase.
(b) amplitude.
(c) frequency.
(d) period.
A wavefront of a wave has direction with wave motion
(A) Parallel
(B) Perpendicular
(C) opposite
(D) at any angle θ
In a Young’s double slit experiment the distance between the slit is 1 mm and the distance of screen from the slit is 1 m. If light of wavelength 6000 A is used then the fringe width is:
(a) 0.4 mm
(b) 0.5 mm
(c) 0.6 mm
(d) 0.8 mm
The SI unit of inductance is the henry. It can be written as
(a) weber/ampere
(b) volt-second/ampere
(c) joul/(ampere)²
(d) ohm-second
The figure below shows a potentiometer with a cell of 2.0 V and internal resistance 0.40 Ω maintaining a potential drop across the resistor wire AB. A standard cell which maintains a constant emf of 1.04 V (for very moderate currents up to a few mA) gives a balance point at 67.3 cm length of the wire. To ensure very low currents drawn from the standard cell, a very high resistance of 600 KΩ is put in series with it, which is shorted close to the balance point. The standard cell is then replaced by a cell of unknown emf Ꜫ and the balance point, found similarly, turns out to be at 82.3 cm length of the wire. What is the value Ꜫ?
(a) 0.25 V
(b) 2.25 V
(c) 3.25 V
(d) 1.25 V
In YDSE, The distance between two consecutive bright and dark fringes are given by:
(a) β=λD/d
(b) β=λd/D
(c) β=λDd
(d) β=λ/Dd
What happens if one of the slits, say S1 in Young’s double , slit experiment-is covered with a glass plate which absorbs half the intensity of light from it?
(a) The bright fringes become less-bright and the dark fringes have a finite light intensity
(b) The bright fringes become brighter and the dark fringes become darker
(c) The fringe width decreases
(d) No fringes will be observed
When interference of light takes place
(a) energy is created in the region of maximum intensity
(b) energy is destroyed in the region of maximum intensity
(c) conservation of energy holds good and energy is redistributed
(d) conservation of energy does not hold good
When a compact disc is illuminated by a source of white light , colored lines are observed. This is due to
I. Interference
II. Diffraction
III. Dispersion
IV. Refraction